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uniq(1) User Commands uniq(1)
NAME
uniq - report or filter out repeated lines in a file
SYNOPSISuniq [-c | -d | -u] [-ffields] [-schar] [ input_file [output_file]]
uniq [-c | -d | -u] [-n] [ + m] [ input_file [output_file]]
DESCRIPTION
The uniq utility will read an input file comparing adjacent lines, and
write one copy of each input line on the output. The second and suc-
ceeding copies of repeated adjacent input lines will not be written.
Repeated lines in the input will not be detected if they are not adja-
cent.
OPTIONS
The following options are supported:
-c Precede each output line with a count of the number of times the
line occurred in the input.
-d Suppress the writing of lines that are not repeated in the input.
-ffields
Ignore the first fields fields on each input line when doing com-
parisons, where fields is a positive decimal integer. A field is
the maximal string matched by the basic regular expression:
[[:blank:]]*[^[:blank:]]*
If fields specifies more fields than appear on an input line, a
null string will be used for comparison.
-schars
Ignore the first chars characters when doing comparisons, where
chars is a positive decimal integer. If specified in conjunction
with the -f option, the first chars characters after the first
fields fields will be ignored. If chars specifies more characters
than remain on an input line, a null string will be used for com-
parison.
-u Suppress the writing of lines that are repeated in the input.
-n Equivalent to -ffields with fields set to n.
+m Equivalent to -schars with chars set to m.
OPERANDS
The following operands are supported:
input_file
A path name of the input file. If input_file is not specified, or
if the input_file is -, the standard input will be used.
output_file
A path name of the output file. If output_file is not specified,
the standard output will be used. The results are unspecified if
the file named by output_file is the file named by input_file.
EXAMPLESExample1:UsingTheuniq Command
The following example lists the contents of the uniq.test file and out-
puts a copy of the repeated lines.
example% cat uniq.test
This is a test.
This is a test.
TEST.
Computer.
TEST.
TEST.
Software.
example% uniq -d uniq.test
This is a test.
TEST.
example%
The next example outputs just those lines that are not repeated in the
uniq.test file.
example% uniq -u uniq.test
TEST.
Computer.
Software.
example%
The last example outputs a report with each line preceded by a count of
the number of times each line occurred in the file:
example% uniq -c uniq.test
2 This is a test.
1 TEST.
1 Computer.
2 TEST.
1 Software.
example%
ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment variables
that affect the execution of uniq: LC_CTYPE, LC_MESSAGES, and NLSPATH.
EXIT STATUS
The following exit values are returned:
0 Successful completion.
>0 An error occurred.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWesu |
+-----------------------------+-----------------------------+
|CSI |Enabled |
+-----------------------------+-----------------------------+
SEE ALSOcomm(1), pack(1), pcat(1), sort(1), uncompress(1), attributes(5), envi-ron(5)
SunOS 5.9 20 Dec 1996 uniq(1)